Sewing machine and method op forming seams



Oct. 29, 1929.. F. w. DAVIDSON SEWING MACHINE AND METHOD OF FORMING SEAMS 0r,iginal Filed June 1925 2 Sheets-Sheet 221 HNLVENTOR 7A-J WWW MQ Vi M v ATTORN E YS Oct. 29, 1929. F. w. DAVIDSON 1,733,867

SEWING MACHINE AND METHOD OF FORMING SEAMS' Original Filed June 1, 1926 2 s t -s 2 I 7 2M100. a6 69 M @mii ATTORNEYS Patented Oct. 29, 1929 UNITED STATES FRANK W. DAVIDSON, F UPPER MON'ICLAIR, NEW JERSEY, ASSIGNOR TO WILLCOX 8t GIBBS SEWING MACHINE COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK SEWING MACHINE AND METHOD OF FORMING SEAIVIS Application filed June 1, 1926, Serial No. 112,995.

This invention relates to new and useful improvements in sewing machines and more particularly to sewing machines wherein edge portions of fabric are upturned in a slot of the presser foot, trimmed in said slot during each pause between intermittent advances of the fabric by the feed of the machine, and then turned down into position for application of stitches thereto to secure the trimmed edges together and thus form a seam.

The invention also relates to a new and useful improved method of forming such seams.

vVhile devised especially with reference to what is known commercially as the WVillcoX & Gibbs Sewing Machine Companys flatlock machineshown for example in patents to Stockton Borton 1,041,574, and to A. A. Merritt 1,041,652, both dated October 15, 1912, and producing the seam of Bortons Patent 883,614, dated March 31, 1908this invention is not restricted to use with any particular type or make of sewing machine.

It has been heretofore proposed to provide movable edge-turning devices, to turn down or assist in turning down an upturned fabric edge after it has been trimmed and before stitches are applied thereto, but said devices, as it has been proposed to actuate them, would be left in the path of the fabric during all or some portion of each feed movement of the fabric. Therefore, in each feed movement the fabric has to be moved forward against and past the edge-turning device occupying a position in the path of movement of the fabric. The resulting drag of the fabric at or near its trimmed edge or edges, tends not only to retard and disturb the feeding but to disarrange the trimmed edge or edges with respect to the desired positioning of said edge or edges in the finished work or seam.

The main object of the present invention is to provide a sewing machine and a method of forming seams in which an edge-turning device, pusher, or finger will act to turn down the fabric edge or edges only while the fabric is standing still between intermittent feed movements thereof and will be withdrawn from the path of the fabric during each said feed movement thereof.

Renewed August 15, 1928.

The aforesaid and other objects and advantages attained by the invention will be further understood by reference to the accompanying drawings illustrating what is now believed to be the preferred embodiment of the invention as applied to a machine of the character of the aforesaid fiatlock machines.

In said drawings- Fig. 1 is a view in front elevation (with parts in section) of the left-hand end or side of the sewing machine, including a portion of the free end of the workarm and a portion of the head of the machine With associated parts;

Fig. 2 is a perspective view of parts shown in Fig. 1 with the addition of fabric edges shown as being operated upon and seamed together by a lapped seam;

Fig. 3 is a top plan view, of the presser foot and parts operating in conjunction therewith;

Fig. 4 is a side elevation looking from what is the right-hand side of the presser foot as the operator faces the forward or slotted end thereof in Figs. 2 and 3;

Fig. 5 is a diagrammatic outline bottom view of the presser foot;

Fig. 6 is a perspective view of the lower end of the trimmer arm and parts attached thereto, with the lapping device shown as detached and moved slightly out of its normal position;

Figs. 7 and 8 are more or less diagrammatic perspective views, F i g. 7 showing the movable trimmer blade and associated lapping device in their withdrawn or retracted positions such as they occupy while the fabric is being fed or advanced by the feeding mechanism, and Fig. 8 showing the positions of the same parts after the movable trimmer knife has made a forward or trinnning movement at a time when the fabric is not being advanced by the feeding mechanism; and

Fig. 9 is a perspective view illustrating the seam as made by three needles with three parallel lines of stitches, instead of four as in the other views.

In many particulars the mechanism illustrated in the drawings is substantially the same as is disclosed in the aforesaid patents.

Portions of the hollow machine frame or casing, such as used in the aforesaid flatlock machine, are shown in the drawings. 20 is a hollow standard at one end of said frame, and 22 is a portion of the free end of a workarm which latter also forms part of the complete frame or Casing. At its upper end standard 20 extends forward and constitutes the head 23 of the machine which partly overhangs the end 22 of the work-arm. 24 is the throat-plate or clotlrplate. is the forward or fulling feed dog and 26 the rearward or stitch feed dog of differential feeding mechanism, both of said feed dogs work ing through slots in the cloth-plate in engaging and intermittently feeding the fabric or work. 27 is a presser-foot bar vertically movable in the machine head 23 and yield ingly pressed downward by the usual coiled spring 28, the tension of which may be adjusted by a nut 29. 30 is a tubular shaft sleeved on and rotatable about the presser foot bar 27. A split hub, 31 embraces and is clamped to the upper end of shaft 30 and a coiled spring 32, surrounding prcsser-foot bar 27, bears at one end against a collar 33 on said bar and at its other end against the upper end of hub 31, thereby tending to yieldingly press said hub downwardly and with it the tubular shaft 30. The machine has trimming mechanism. An arm 34 formed integrally With the hub 31 extends downward through an opening in the bottom wall of the head 23 of the casing and at its lower end carries a movable blade 35 which cooperates with a fixed blade 36. Driving connections including a pitman 37 (part only of which is shown in Fig. 1) having a universal joint connection 38 to the outer end of an arm 39 formed integral with the hub 31., serves to oscillate the said hub 31, its depending arm 34 carrying trimmer-blade 35, and the tubular shaft 30, about the presser-foot bar 27. An arm 40 on the lower end of tubular shaft 30 is connected at its outer end by link 41 to an arm 42 clamped onto the upper end of a short vertical shaft 43 (Fig. 1) which latter at its lower end carries a cross-thread hook 44. A long curved arm 45, integral at one end With arm 42, at its other end is conncctec by a link 46 to a crank-arm 47 at the upper end of a short shaft 48 journalled in an upright bearing opening in the body of the presser-foot. Cross-thread carrier 49 is detachably secured to the lower end of the shaft 48. The cross-thread hook 44 and carrier 49, operate in the manner set forth in the patents aforesaid.

50 is the needle-bar working in the machine head and, in the particular type of machine shown, carrying four needles 51. Parts of the presser foot lifting means are also illustrated. 52, Fig. 1, is, the outer one. of a lever arm of suitable prcsser-foot lifting; means, such as shown in. the before-mentioned patents, said lever reaching forward under the overhanging head of the machine so that its said end normally lies under the lower end of the presser-foot bar 27 with slight clearance, whereby when the presser-foot lifting means is actuated by its hand-lever or treadle said arm 52 engages and lifts said bar and with it the resser-foot and associated parts. 57, Fig. 1, are thread-carrying loopers, one for each of the four needles and cooperating therewith beneath the throat-plate when the needles are down, and 58 is a movable loop spreader, these parts also cooperating in the manner more fully set forth in the patents aforesaid.

In many particulars the presser-foot herein illustrated is substantially that of Figs. 46 and 47 of the aforesaid Merritt Patent No. 1,041,652. 60 is the main body of the foot having a split hub adapted to be securely clzunped, to the lower end of the presser-foot bar 27. The horizontally disposed flattened portion of the foot body which extends folward. of what constitutes the shank of the foot, is recessed, notched or slotted, forming two toes or branches 61 and between which the upturned edges of fabric advance and are trimmed by the trimmer-blades. The fixed lower trimmer-blade 36 projects through and rigidly but adjustably and removably see cured in a horizontal opening through the toe 61 of the presser-foot near the rear end of the fabric guide slot or channel. The clamp block 63 and screw 64 serve to thus secure the fired lower trimmer-blade in place. The movable upper trimmer-blade 35, works in a horizontal passageway or opening through the toe portion 62 of the presser-foot at or near the rear end of the fabric guiding-slot or channel, said movable blade being clamped to the lower end of the trimmer-arm 34 by a clamp-shoe or plate 65 hearing along the top of the blade, and a stirrup or strap 66. pass]- ing across the bottom of the outer end of the blade and secured by screws to the lower end of the trimmer-arm 34. The trimmer-blade 35 has a finger or extension projecting beyond its cutting edge and bearing upon the top surface of the lower or fixed trimmer-blade 36, as clearly shown in Figs. 7 and 8.

To deflect to one side the trimmings re moved by the trimmer-blades, there is a deflector secured by a pivot screw 71 to. the forward end of the toe 62 of the presser-foot. his deflector may be swung on its; pivot screw from its normal position in which it is shown in Figs. 1 and 2 of the drawings, to a position such as shown in Fig. 3, to thereby give ready access to. the necdles,cross-tl-1read hook and cross-thread carrier. 75 is avneedle opening through the presser-foot through which. the four needles 51 work, and 76 is a yielding chaining ofi' section of the bottom of the presser-foot positioned in an opening to the rear of the needle opening and operating in the manner more fully set forth in the patents aforesaid.

The parts as thus far described by the use of reference numerals are substantially the same as corresponding parts heretofore embodied in the aforesaid commercial flatlock machines and described in the hereinbefore mentioned patents.

80 is a movable edge-turning finger, pusher or device, from which a shank extends up ward at right angles in part 81 and then horizontally at right angles in part 82, the latter having openings therethrough for two screws 83 by which the edge-turning pusher is rigidly secured to the lower end of arm 34 which as before explained constitutes a carrier to which the movable trimmer-blade is secured. The pusher 80 works in and through a horizontal passageway or slot 8% through the toe portion 62 of the presserfoot. The outer end of the pusher 80 where it engages the fabric is curved and thus tapered so that it projects furthest, at what is its rear edge in the direction of feed of the fabric. As thus appears, the pusher 80 is positioned to be moved into and out of engagement with the fabric after the trimmer-blades have acted thereon but before the fabric reaches the needles.

A and B in Figs. 2, 7, 8 and 9, are portions of fabric the edges a and Z) of which are to be trimmed and then oined together. A and B may be portions of a single piece of fabric, or of separate pieces. The fabric A and B, with the edges a and 6 turned up together in the slot of the presser-foot, as shown in 9., is intermittently fed step by step to the trimming mechanism and stitch-forming mechanism. During each period of rest between feed movements, the needles penetrate the fabric and the movable trimmer-blade 35 is given its forward cutting stroke and returned. Moving with said movable blade, the pusher 80 moves into action against trimmed edge a, as shown in Fig. 8, and with the cooperation of the presser-foot turns said upstanding edge a down into position to be overlapped by the trimmed edge Z) which is turned down by the action of the bottom surface of "he presser-foot. By its formation and by the movements imparted to it by being mounted on the carrier of the movable trimmer-blade, the pusher is out of the path of the fabric during each feeding movement of the fabric, and only acts upon the fabric during periods of rest between feed movements.

Fig. 9 shows three rows of needle stitches instead of four as in Figs. 1, 7 and 8.

\Vhat is claimed as new is:

1. In a sewing machine, the combination of horizontally operating trimming mechanism adapted to trim an edge of fabric while said edge is turned up out of the general plane of the body of the fabric; stitch-forming mechanism for applying stitches to said trimmed edge after it has been turned down into the general plane of the body of the fabric; feeding mechanism acting to feed the fabric to the trimming mechanism and then to the stitch-forming mechanism by intermittent feed of the fabric; and means for turning said edge down after it is trimmed and before the stitches are applied thereto, said means including a pusher or edge-turning device actuated to impart turning-down movement to said trimmed edge between the feed movements of the latter by the feeding mechanism and to be withdrawn from the path of the fabric during each of said feed movements thereof.

2. In a sewing machine, the combination of a horizontally operating trimming mechanism adapted to trim two edges of fabric while turned up together out of the general plane of the body of the fabric; stitch-forming mechanism adapted to apply stitches to said trimmed edges after they have been turned down in close proximity to each other in the general plane of the body of the fabric; feeding mechanism acting to feed the fabric to the trimming mechanism and then to the stitch-forming mechanism by intermittent feed movements of the fabric; and means acting upon the trimmed edges between the trimming mechanism and the stitch-forming mechanism to turn the edges down, said means including a pusher or edge-turning de vice actuated to impart turning down movement to one of said trimmed edges between the feed movements thereof by the feeding mechanism and to be withdrawn from the path of the fabric during each of said feed movements thereof.

3. In a sewing machine, the combination of a horizontally operating trimming mechanism adapted to trim two edges of fabric while turned up together out of the general plane of the body of the fabric; stitch-forming mechanism adapted to apply stitches to said trimmed edges after they have been turned down into overlapped relationship to each other; feeding mechanism acting to feed the fabric to the trimming mechanism and then to the stitch-forming mechanism by intermittent feed movements of the fabric; and means acting upon the trimmed edges between the trimming mechanism and the stitch-forming mechanism to turn the edges down into overlapped relationship. said means including a pusher or edge-turning device actuated to impart turning down movement to one of said trimmed edges between the feeding movements thereof by the feeding mechanism and to be withdrawn from the path of the fabric during each of said feed movements thereof.

4. In a sewing machine, the combination of feeding mechanism; trimming mechanism adapted to trim an edge of fabric while said edge is turned up out of the general plane of the body of the fabric and including a movable blade acting approximately horizontally; stitchaforming mechanism for applying stitches to said trimmed edge after 1t has been turned down into the general plane of the body of the fabric; and a movable edgeturning device or pusher operating approximately horizontally and acting upon t 1e upturned fabric edge after it has been trimmed and before stitches are applied thcrct said device being actuated to make forward and return movements simultaneously with the forward and return movements of the movable trimmer blade.

5. In a sewin machine, the combination of feeding mechanism; trimming mechanisn adapted to trim an edge of fabric while said edge is turned up out of the general plane of the body of the fabric and including a movable blade acting approximately horizontally, a carrier to which said blade is secured, and means for imparting forward and return movements to said carrier and blade; stitchftirn'iing mechanism for applying stitches to said trimmed. edge after it has been turned down into the general plane of the body of the fabric; and a movable edge-turning device or pusher operating approximately horizontally and acting upon the upturned fabric edge after it has been trimmed and before stitches are applied thereto, said do ice being mounted on the aforesaid carrier for the movable trimming blade to make its forward and backward movements simultaneously with the forward and backward mov'ements of said blade.

(3. In a sewing machine, the combination of ceding mechanism operating to intermitently feed the work; trimming mechanism adapted to trim an edge of fabric while said edge is turned up out of the general plane of the body of the fabric and including a movable blade, a carrier to which said blade is secured and means for imparting forward and return movements to said car'ier and blade; stitch-forming mechanism for applying stitches to the trimmed edge of fabric after it has been turned down into the general plane of the body of the fabric; and movable edge-turning device or pusher secured to the carrier of the movable blade and actuated thereby to act upon the trimmed fab ic ed 7e between feed movements thereof by the reediug mechanism and to be withdrawn from the path the orie during each such feed movement thereof.

7. The combination of stitchforming mechanism, horizontally disposed trimming devices located in admnce of the stitch-fond ing mechanism and adapted to trim an upturned edge portion of fabric; feeding mechanism operating to intermittently feed the fabric; and means operating between the trimming devices and stitclrforming mechanism for turning down said upturned trimmed edge portion of fabric prior to the stitching of the same, said turning-down means being movable in a plane substantially parallel with the general plane of the fabric and being moved to act upon the fabric between the intermittent feed movements thereof and to be Withdrawn from the path of the fabric during each said feed movement thereof.

The combination of stitch-forming mechanism; trinnning devices located in advance of said stitching mechanism including a trimmer blade movable in a horizontal plane; and a turning finger acting in rear of said trimming devices and in advance of the stitch-forming mechanism upon an upturned edge of fabric trimmed by the former, linger being movable with said movable tranmer blade to make turning i with the cutting "n the path of the fabric be- 'e-turning strokes.

combination of stitch-forming in 3 trimming mechanism including -e t-rin'imer blade and a carrier there- 'pon "corned edge of fabric after it s been trimmed by the trimming mecha- "I to 'il-Llli'l said edge down into a horiplane, said turning linger maxing i l and 'eturn movements simultaneously with the forward and return move- 7 of the movable blade.

1"). The improved method consisting in tllllllll the edge of fabric up out of the general plane of the body of the fabric; 'mming said edge by a trimming mechaiism while so turned up; turning the rimmed edge down into the general plane of the body of the fabric and applying stif' ches thereto by a stitch-forming mechaeeding the fabric to the trimming nsm; meslmnism and then to the stitch-forming mechanism by intermittent feed movements imparted thereto by a feeding mechanism; .d in the aforesaid turning down of the trimmer. edge acting upon said edge, between the trimming thereof by the trimming mechanism and the application of stitches thereto by the stitch-forming mechanisn'i by a mechanically actuated pusher or edge-turndevice which. imparts turning down movement to the fabric edge between the feed movements of the latter by the feeding mechan sm and is withdrawn from the path of the fabric during each feed movement thereof by the feeding mechanism.

11. The improved method of uniting two portions of fabric, consisting in bringing said portions together from opposite directions and turning the edges thereof together up out of the general plane of the body of the fabric; trimming said edges by a mechanically actuated trimming mechanism while they are in such turned up position; turning the trimmed edges down into close proximity to each other in the general plane of the body of the fabric and securing the edges together in that relationship by stitches made by a stitch-forming mcc ianism; feeding the fal ric to the trimming mechanism and then to the stitch-forming mechanism by intermittent feed movement imparted thereto by a feeding mechanism; and in the aforesaid turning down of the trimmed edges acting upon one of said edges between the trimming thereof by the trimming mechanism and the application of stitches thereto by the stitch-forming mechanism, by a mechanically actuated pusher or edge-turning device which imparts its turning down movement to the fabric edge between the feed move ments of the latter by the feeding mechanism and is withdrawn from the path of the fabric during each feeding movement thereof by the feeding mechanism.

12. The improved method of uniting two portions of fabric consisting in bringing said portions together from opposite dir ctions and turning the edges thereof together up out of the general plane of the body of the fabric; trimming said edges by a mechanically actuated trimming mechanism while they are in such turned up position; turning the trimmed edges down into overlapped relationship to each other and securing the edges together in that relationship by stitches made by a stitch-forming mechanism; feeding the fabric to the trimi'ning mechanism and then to the stitch-forming mechanism by intermittent feed movements impartet thereto by a feeding mechanism; and in the aforesaid turning down of the trimmed edges acting upon one of said edges, between the trimming thereof by the trimming mecha nism and the application of stitches thereto by the stitch-forming mechanism, by a mechanically actuated pusher or edge-turning device which imparts its turning down movement to the fabric edge between the feed movements of the latter by the feeding mechanism and is withdrawn from the path of the fabric during each feed movement thereof by the feeding mechanism.

13. The combination of stitch-forming mechanism; trimming devices located in ad- Vance of the stitclrforming mechanism and adapted to trim an upturned edge portion of fabric feeding mechanism operating to intermittently feed the fabric; and means operating between the trimming devices and stitchforming mechanism for turning down said upturned trimmed edge portion of fabric prior to the stitching of the same, said turning-down means being movable in a plane substantially parallel with the general plane of the fabric and being moved to act upon the fabric between the intermittent feed movements thereof and to be withdrawn from the path of the fabric during each said feed movement thereof.

14. The combination of stitch-forming mechanism; trimming mechanism including a movable trimmer blade; an edge turning finger; and means actuating said finger simultaneously with the cutting movements of the movable trimmer blade to act upon an upturned edge of fabric after it has been trimmed by the trimmer mechanism to turn said edge down into a horizontal plane.

15. In a sewing machine, the combination of trimming mechanism adapted to trim an edge of fabric while said edge is turned up out of the general plane of the body of the fabric; stitch-forming mechanism for applying stitches to said trimmed edge after it has been turned down into the general plane of the body of the fabric; feeding mechanism acting to feed the fabric to the trimming mechanism by intermittent feed of the fabric; and means for turning said edge down after it is trimmed and before the stitches are applied thereto, said means including a pusher or edge-turning device actuated to impart turning-down movement to said trimmed edge between the feed movements of the latter by the feeding mechanism and to be withdrawn from the path of the fabric during each of said feed movements thereof.

16. In a sewing machine, the combination of trimming mechanism adapted to trim two edges of fabric while turned up together out of the general plane of the body of the fabric; stitch-forming mechanism adapted to apply stitches to said trimmed edges after they have been, turned down in close proximity to each other in the general plane of the body of the fabric; feeding mechanism acting to feed the fabric to the trimming mechanism and then to the stitch-forming mechanism by intermittent feed movements of the fabric; and means acting upon the trimmed edges bet-ween the trimmingmechanism and the stitch-forming mechanism to turn the edges down, said means including a pusher or edge-turning device actuated to impart turning down movement to one of said trimmed edges between the feed movements thereof by the feeding mechanism and to be withdrawn from the path of the fabric during each of said feed movements thereof.

In testimony whereof I have signed this specification.

FRANK IV. DAVIDSON. 

